1. Field of the Invention
The present invention relates to a multi-channel tuning receiver and a multi-channel tuning method thereof, and more particularly, to a multi-channel tuning receiver that can receive a plurality of independent channels, separate the plurality of independent channels from each other by a channel bandwidth of each independent channel based on a central frequency and thereby can combine the plurality of independent channels into a single signal.
This work was supported by the IT R&D program of MIC/IITA. [2006-S-019-02, The Development of Digital Cable Transmission and Receive System for 1 Gbps Downstream]
2. Description of Related Art
Cable modems of standards less than Data Over Cable Service Interface Specifications (DOCSIS) 2.0 receives a signal of 54 MHz through 864 MHz from a Hybrid Fiber Coax (HFC) network to reduce the band of the signal to an intermediate frequency (IF) bandwidth, generally 44 MHz, using a radio frequency (RF) tuner, tune the signal, and perform digital demodulation for the tuned signal of 6 MHz. However, in cable modems of standards greater than DOCSIS 3.0, a physical layer protocol (PHY) should simultaneously receive a signal that is bonded with at least four channels, convert the received signal into a digital signal, and then transfer the digital signal to a Media Access Control (MAC) module.
FIG. 1 is a block diagram illustrating the structure of a receiver 100 for receiving a single channel according to a conventional art. Referring to FIG. 1, the receiver 100 includes an RF tuner 102, an analog-to-digital (A/D) converter 104, and a demodulator 106.
The RF tuner 102 may receive, tune, and output an RF signal from the HFC network. The A/D converter 104 may receive a tuned analog signal from the RF tuner 102, convert the analog signal to a digital signal, and output the digital signal. The demodulator 106 may receive the digital signal from the A/D converter 104 and the digital signal.
The receiver 100 may process only the single channel. Accordingly, in order to receive multiple channels, a plurality of receivers constructed as above should be connected in parallel and thereby be used.
When using the parallel-connected receivers for receiving the single channel, an analog signal is converted to a digital signal for each channel. Therefore, a plurality of A/D converts should be used in order to receive multiple channels.